Floor grinding machine



1960 L. BIASONI 2,923,107

FLOOR GRINDING MACHINE Filed March 11, 1957 I a Sheets-Sheet 1 INVENTUR LUIGI BIASONI Feb. 2, 1960 BIASONI FLOOR GRINDING MACHINE 3 Sheets-Sheet 2 Filed March 11, 1957 INVE NTUR LUIGI BIASONI Feb. 2, 1960 L. BIASONI FLOOR GRINDING MACHINE 3 Sheets-Sheet 3 Filed March 11. 1957 INVENTU R LUIGI amsom United ates Patent 9 FLOOR GRINDING MACHINE Luigi Biasoni, Toronto, Ontario, Canada, 'assignor to Granell Manufacturing Limited, Toronto, Ontario, Canada Application March 11, 1957, SerialNo. 645,145 2 Claims. (Cl. 51-177) This invention relates to improvements in floor grinding machines, particularly to machines of the type employed in the grinding and polishing of terrazzo flooring and the like.

The principal object of the invention is to provide a grinding machine of the above nature of sturdy and economical construction, which machine will enable grinding or polishing to be carried out much more rapidly and economically than with present machines.

Another and important object is to provide a machine having such improved grinding and polishing ability which machine will be lighter and more compact than present machines, so that it can be handled and manipulated much more easily to facilitate both the grinding operation and transportation from jobsite to jobsite. In this connection, it is an important object to greatly reduce the size of motors required in grinding machines of this type and still provide an extremely high capacity machine whereby an important saving in cost of manufacture and weight factor is achieved.

Another important object is to provide a machine as aforesaid which will more effectively utilize the grinding elements so that they will be more effective in their grinding and will give a much greater grinding life.

Still another important object is to provide a grinding machine which will be adjustable both from the standpoint of continuously presenting the grinding elements in proper grinding relation, but also to continuously accommodate the height of the operator.

Again an important object is to provide a grinding machine having a balanced arrangement of the component assemblies to provide optimum weight distribution for grinding while reducing the overall weight.

Still another important object is to provide a machine which incorporates its own source of liquid, normally water, for wetting the grinding elements and surface being ground, and which will automatically effect optimum distribution of such liquid to facilitate the grinding action.

According to one feature of the invention the grinding machine utilizes a grinding assembly comprising a grouping of grinding elements rotating about a central axis, and means are arranged to deliver liquid within the grouping to flow outwardly therefrom whereby adequate wetting of the grinding elements and the actual floor surface being ground is effected.

According to another feature of the invention, the grinding elements depend from the body of the machine which is adjustably or pivotally supported at a point remote from the grinding assembly from a wheeled carriage, and means are provided for adjusting the body relative to the carriage to maintain the grinding elements in proper grinding relation to the floor surface as wear occurs on these elements.

Another important feature resides in utilizing the motor and the other grinding element drive components as a means of loading the grinding elements by disposing such components on the grinding element side of the point of attachment of the body to the wheeled carriage.

2,923,107 Patented Feb. 2, 1960 Still another important feature resides in providing a tank for the reception of water or other grinding element and floor surface wetting liquid on the body of the machine and so disposing the tank that the contained liquid also serves to load the grinding elements to facilitate grinding. V

In this connection, it is a feature to provide a simple means of adjusting liquid flow to Within the grinding element grouping.

Still another important feature resides in adjustably mounting a handle on the machine body at a point on the opposite side of the connection between the body and carriage to the grinding elements to provide a leverage control of the machine, and further providing a simple and convenient locking means for locking the handle in adjusted positions to suit the convenience of the operator.

These and other objects and features will become apparent from the following description taken in conjunction with the accompanying drawings, in which:

Figure l is a perspective view, partly broken away, of a grinding machine constructed in accordance with the invention;

Figure 2 is an enlarged side-elevational view of the machine of Figure 1;

Figure 3 is a part top plan, part horizontal sectional View, of the machine of Figures 1 and 2;

Figure 4 is a front elevational view, partly broken away, of the machine;

Figure 5 is an underside plan view of the gear case assembly and grinding assemblies;

Figure 6 is a fragmented vertical sectional detail taken through one of the spindles and associated grinding assemy;

Figure 7 is an exploded perspective view of the gear case carrying platform and undercarriage assembly;

Figure 8 is a part sectional, part perspective view of the liquid distribution control valve for regulating liquid flow to the grinding assemblies, and

Figure 9 is a fragmentary mid-vertical sectional detail of the liquid flow control unit.

Referring first to Figures 1, 2 and 7, the grinding machine comprises a gear case assembly, generally designated at 1, from which depend a pair of grinding assemblies, designated at 2, and secured to one side of the gear case 1 is a platform 3, beneath which is pivotally secured an undercarriage assembly, generally designated at 4.

As seen in Figures 1, 4 and 6, the gear case assembly 1 comprises a lower gear case 5 in the form of a pan casting and a cover casting 6. The gear casing members 5 and 6 are formed with a pair of vertically registering bosses 7 and 8, respectively, as best seen in Figure 6, in which are mounted roller bearing bushings 9, the bushings 9 of each pair of the registering bosses 7 and 8 supporting a spindle 10 on which is keyed a gear 11 mounted within the gear case member 5. As will be seen in Figure 3, the arrangement is such that the gears 11 mounted on the spindles 10 mesh, and one of the gears is driven through a pinion 12 driven by a motor 13 mounted on the gear case cover member 6.

As will be seen from Figure 6, each of the spindles 10 projects below the lower gear case member 5 and carries a tri-armed shoe 14 keyed thereto at the lower end. Each of the shoes 14 is held in place by a nut 15 threaded on a threaded extension at the lower end of the respective spindle 10, and a retaining nut 16 and washer 17 threaded on the upper end of each of the spindles 10 completes the spindle assembly. Each of the shoes 14 has bolted thereto a plurality of resilient rings 18 of heavy rubber orother suitable material and bolted to these arrangement, the grinding elements are resiliently connected to the lower end of the respective spindle and present bottom faces 21 adapted to engage a surface 22 to be ground. A heavy coil spring 23, surrounding the lower end of each of the spindles 10 is disposed between each of the grinding element holders 19 and its respective shoe 14, surrounded by a casing 7'.

Each of the spindles 10 is provided with a central bore 24, and each of the holders 19 is provided with a central opening 25 registering with the respective spindle bore 24, and closing the top of each of the cover bosses 6 is a cover disc 26 carrying a depending tube 27 which projects through the respective spindle bore 24 and holder opening 25. Each of the cover discs 26 is provided with a central crown 28 having a lateral bore 29 which communicates with the depending tube 27, and mounted .in this bore is a tube 36.. Each of the tubes 30 is connected by means of a flexible tube 31 to a flow control device generally designated at 32 mounted on the gear case cover 6, as shown particularly in Figures 1, 8 .and '9. This flow control device is mounted within a wall 33 secured to the top of the gear case cover .6 and forming with the gear case cover a liquid or water receiving tank.

The flow control device 32 is shown as comprising a valve body 34 having a valve seat 35 at the bottom of an internally and externally threaded tubular portion 36, the valve seat leading to a pair of discharge tubes 37 .connected to the flexible tubes 31. A spindle 3.8, suitably supported by means of a bracket 39 mounted on the tank wall 33, carries a threaded sleeve 40, threadably engaging in the tubular portion 36 of the valve body whereby upon rotation of the spindle by means of a suitable control handle or wheel 41 the spindle 38 can be moved to and from the valve seat 35.

A ported housing 42 is threaded on the exterior of the tubular portion 36 of the valve body 34, and the portion .36 is provided with ports 43 therethrough to direct liquid entering the housing 42 through into the valve body, as indicated by the arrows in Figure 9.

It will be understood that, upon operation of the motor 13 to drive the pinion 12 and hence gears 11, the grinding elements 20, which are grouped about the spindle 10 of their respective holders 9, will sweep out a circular path centered on the axis of rotation formed by the respective spindle 10. At the same time, water or liquid contained within the tank wall 33 will be delivered in accordance with the setting of the valve spindle 38 downwardly through the hollow spindles 10 and through the holder openings 25 to the area within the path being swept out by the grinding elements.

As best seen in Figures 3 and 7, the platform 3 has a depending flange 44 by means of which the gear case assembly 1 is bolted thereto, and this flange 44 carries on its inner face pivot lugs 45 to which is pivoted an undercarriage structure 46 forming part of the undercarriage assembly 4. This undercarriage or sub-frame structure 46 extends outwardly from the gear case assembly 1 beneath the platform 3 as a cantilever member, and is provided at a point remote from the pivot axis constituted by the pivot bolts 47 with a pair of depending webs or lugs 48, between which is pivoted by means of a pivot lug 49 an axle housing 50 carrying ground engaging wheels 51 at the ends thereof. It will be seen from Figure 3 that the axis of rotation of the wheels 51 is parallel to the pivot axis 47 of the undercarriage or sub-frame 46, and the pivot axis of the axle housing 50 is perpendicular thereto.

As shown in Figures 1, 2 and 7, the platform 3 has an opening 52 therethrough, and surrounding this opening and projecting above the platform is a circular wall 53 to which is bolted an upright generally conical housing 54 having a bottom mounting flange 55. Projecting downwardly within this housing 54 is an operating screw 56 4 formed with a shoulder 57 abutting the underside of the top of the housing 54, and held in abutment therewith by .means of a nut 5.8 threaded on a threaded extension projecting above the housing. A hand wheel 59 is provided for rotating the screw 56.

A tubular T-member 60 has its head pivoted between lugs 61 formed on the upper side of the undercarriage or sub-frame 46 and projects upwardly therefrom through the housing opening 52 to receive and threadably engage with the screw 56, as best seen in Figure 2. Thus, rotation of the screw 56 effects a pivotal movement of the undercarriage 46 about its pivot axis 47 to move the wheels 51 towards and from the underside of the platform 3.

At a point remote from the gear case assembly 2, the platform 3 is provided with upstanding pivot lugs 62, one at each side thereof, and pivoted thereto is a handle 63 including a pair of spaced depending arms 64 formed at their lower ends with arcuate lateral extensions 65 which, on pivoting of the handle, swing between depending sides 66 of the platform and guides 67. These extensions 65 are formed with a plurality of holes 68 therein stru k n the arc of a circle, adapted to be .seleetively engaged by means of rods 69, Figure 3 mounted to side axially through the sides 66 of the platform. These rods .69 are supported at their inner ends by means of lugs 70, and are actuated by springs 71 to retract inwardly out of engagement with the handle extensions 65. A spindle 72, rotatably supported in a cover 73 of a boss formation 74 on the upper surface of the platform, carries cam projections 75 to engage the heads of the rods 69, as seen in .Figure 3, to actuate these outwardly against the action of the springs 71, interlocking engagement with the holes in the extensions 65 of the handle arms 64 when the spindle is rotated to the stop position against the stop 76.

Thus, the spindle 72 may be rotated to clear the cam projections 7.5 from the inner head ends of the rods 69 to allow retraction of the rods from the handle holes 68, allowing pivotal movement of the handle to the requisite height, whereupon a reverse turning of the spindle 72 will extend the rods and engage them in the registering holes 68, locking the handle in the adjusted position.

As shown in Figure I, particularly, the cover 6 of the gear case assembly is preferably formed with a pair of parallel hollow ribs 77 which serve both to strengthen and add mass to the cover, and also provide a means of conveniently carrying the machine upon the insertion of carrying rods through the passages defined within the ribs.

It will be understood that the gear case assembly ,1 will normally be filled with a suitable grease or lubricant, to which additions may be made from time to time through a suitable access opening closed by fitting 78, Figures ,1 and 3.

As will :be seen from Figure 2, in operation the body .of the machine which is comprised by the gear case assembly 11 and the platform .3 is .disposed generally horizontally with the weight being distributed between the grinding elements 20 and the ground or floor engaging wheels 51. In thisconnection, .it will be appreciated that the drive for the grinding assembly 2, the tank 33 and contained liquid, and even the motor 13, will be disposed substantially directly over the grinding elements 20 to apply downward force thereon.

The body of the machine comprised by the assembly 1 and the platform 3 may be considered as being fulcrumed on the wheels 51 with the mass of:the gear case assembly 1, motor, tank and liquid displaced at a .point remote from the fulcrum at one side thereof, "while the operators handle 63 projects on the opposite side of the fulcrum.

When'the grinding elements or stones 20 are new and not worn, the undercarriage .or sub-frame 46 will be swung on its pivots 47 so that the wheels 51 will be displaceddownwardly relative to the platform, or rather, the

platform will be raised relative to the wheels with the grinding elements flat on the surface 22 to be ground, as seen in Figure 2; As grinding is carried out, the grinding elements are rotated in their circular path while liquid, usually water, is delivered within the path swept out by each of the grinding element groupings. By this arrangement, the water or liquid builds up within the grinding element groupings, and must flow out radially to out across the path being swept out by the elements. With this arrangement, a continuous and adequate wetting of the surface being ground and the grinding elements is achieved, whereas, with conventional machines where water is simply placed on the surface ahead of the grinding elements, the grinding elements simply push or displace the Water ahead of them and adequate wetting of the surface being ground is not effected.

Because of the excellent wetting achieved, and the weight distribution effected, a motor 13 of much smaller capacity and greater speed than previously considered possible can be employed and the machine will provide a rate of grinding not heretofore obtainable.

As the grinding elements or stones 20 commence to Wear, the body of the machine will commence to tip about its fulcrum on the wheels 51 to lower the forward portion of the gear case assembly 1. When this occurs, by adjusting the control screw 56, the platform 3 may be lowered relative to the wheels 51 with the T-member 60 and lugs 61 moving up through the platform opening 52 to bring the body of the machine comprised by the gear case assembly and platform back into a substantially horizontal position, so that all of the grinding elements will be Worn uniformly with the bottom faces 21 thereof being maintained at all times substantially perpendicular to the driving spindles 10.

It will be understood that various modifications in details and arrangements of the parts and in the specific means for carrying out the adjustments in controls hereinabove described may be made without departing from the spirit of the invention or scope of the appended claims.

What I claim as my invention is:

l. A grinding machine comprising a substantially horizontal gear case assembly housing a pair of intermeshing gears, a spindle having a central bore, and being secured to each of said gears and projecting downwardly from said gear case assembly, a motor for driving said gears mounted on said gear case assembly, a grinding element holder resiliently secured at the lower end of and substantially centered on each of said spindles, said grinding element holder having a central opening therethrough registering with said central bore, a plurality of surface engaging grinding elements removably secured to each of said holders and grouped about the axis of the respective spindle to which the holder is secured, a tank adapted to be filled with liquid, conduit means leading from said tank to each of said spindle bores to deliver liquid through the respective central bores and holder, openings to deliver liquid within each grinding element group, a substantially horizontal platform rigidly secured to and extending laterally from one side of said gear casing assembly, an undercarriage pivoted as a cantilever member to one of said platform and gear case assembly and extending laterally from said gear case assembly from its pivot axis beneath said platform and being provided with a pair of ground engaging wheels remote from and rotating about an axis parallel to said pivot axis, adjusting means carried by said platform and operatively connected with said undercarriage to pivot said undercarriage about its pivot to adjust said ground engaging Wheels towards and from said platform, and handle means extending upwardly from said platform to the side thereof opposite to said gear case.

2. A machine as claimed in claim 1 in which said handle is pivotally mounted to swing on an axis disposed parallel to said undercarriage pivot axis, said handle being provided with an arm extending perpendicular to the handle pivot axis, said arm having a series of openings therein and slidable bar means carried by said platform are provided to slide in a direction parallel to said handle pivot axis to selectively engage in said arm means, and means for actuating said slidable bar means.

References Cited in the file of this patent UNITED STATES PATENTS 1,980,491 Mall Nov. 13, 1934 2,097,730 Mall Nov. 2, 1937 2,106,033 Mall Jan. 18, 1938 2,171,060 De Spirt Aug. 29, 1939 2,316,886 Pascucci Apr. 20, 1943 2,793,476 Lombardo May 28, 1957 

